Gadget Master

This clever chap has developed a cheap and easy to build 22 watt amplifier.

Quite compact, the audio amplifier can be used with a car audio system, a booster for speakers in a home theatre stereo system, or to give your computer's speakers some extra power.

The audio amplifier uses a 39K ¼ watt resistor, two 10uf 25V electrolytic capacitors and one TDA 1554 two channel audio amp chip.

The circuit is ideally suited to 4 ohm speakers, but 8 ohm units will also work well. As it dissipates around 28 watts of heat, a good heatsink is necessary. The chip should run cool enough to touch with the proper heatsink installed. The audio amplifier operates at 12 volts at about 5 amps at full volume. Lower volumes use less current and will generate less heat. A printed circuit board is preferred, but a universal or perf board will be fine. Electronics engineers who decide to try this at home should keep lead length short.